Electrical grounding rods are required to insure that line electrical apparatus, for example, electrical power transmission systems and the sub-stations connected therewith as well as telephone lines, are kept at earth potential. Steel structures such as oil well derricks and windmills should be grounded as a precautionary measure against lightning strikes. Lightning arrester systems to protect structures extending well above ground level must be grounded. In the past, grounding rods have been of various lengths and have been hollow or solid and generally have terminated with a short portion of the grounding rod projecting above ground. Hollow rods were driven into the ground using a point of a hard metal to which one end of the rod was attached or on which the hollow end rested. A wooden rod was inserted into the hollow grounding rod into contact with the point. In some instances the other end of the wooden driving rod was struck with a hammer-like device. In other instances the other end of the wooden driving rod has a weight attached thereto, and the rod was moved up and down inside the hollow grounding rod. (see U.S. Pat. Nos. 1.147,791; 1.962,758; 2.145.420 and 2.147.828 ). To use these devices it was necessary for the operator to stand on some object which would enable him to bring the necessary force onto the top of the device (see 21147.828). An improvement over these devices is disclosed in U.S. Pat. No. 4.335.622 wherein a soil gas sampling probe is driven into the soil by means of a collar which is secured to the probe as an anvil and a cylindrical mass is slipped over the probe and strikes the anvil as a hammer by raising it up and bringing it down into contact with the anvil. This device will permit driving the probe into the ground until only that length represented by the depth of the collar and length of the hammer is left above ground level.
The National Electrical Code has established that grounding rods shall be 8 feet in length, generally of solid stock and shall be driven into the ground so that the top of the rod is about 12 inches below ground level. The first above-described devices can meet this requirement but are difficult to initiate the driving. The last above-described device eases the the task of driving the rod into the ground but must be removed and a hammer used to drive the remaining length of the rod below the ground level or a deeper hole must be initially dug.